One-Step Forensic Sexual Assault Casework DNA Purification Kit

Introduction

Sexual assault cases (also called Rape cases) are some of the most challenging and sensitive cases for forensic scientists and law enforcement. Sexual assault cases require a clear male DNA profile in order to analyze autosomal DNA. However, mixed DNA samples collected from female victims may contain only a trace level of sperm cells mixed with excessive female epithelial cells. Hence, separating male DNA from female DNA is crucial in analyzing these cases. Differential lysis is the most popular approach for sperm DNA isolation, but the process is time-consuming and causes significant male DNA loss. Hygia Sexual Assault Casework DNA Purification Kit offers a solution to these technical difficulties.

Differential Lysis Method

Differential lysis is a method of selectively lysing and isolating DNA from a mixture of sperm and epithelial cells. The epithelial cells are lysed first with a lysis buffer without DTT, and the remaining intact sperm cells are collected by centrifugation. The sperm cells are then lysed with a lysis buffer containing DTT, and the released DNA is purified by phenol/chloroform extraction or silica membrane column. Although this method is effective, it is time-consuming, causes significant DNA loss, and lacks reproducibility in sample preparation.

Principle of sexual Assault Casework DNA Isolation

The Hygia kit provides quick and efficient extraction of male DNA after differential Lysis from trace sexual assault samples. The kit uses negative selection chromatography magnetic beads to quickly capture impurities (PCR inhibitors) and leave the male DNA untouched, reducing the risk of DNA loss and buffer carryover from the traditional bind-wash-elute technique. The kit provides a rapid and cost-effective way to purify DNA and is compatible with many different automated liquid handling systems.

Workflow and Purification Results

1. Add Lysis Buffer to break the epithelial cells and release their DNA.

2. Centrifuge to remove all epithelial cell DNA.

3. Add Lysis Buffer P to lyse the sperm cells to release sperm DNA.

4. Mix the lysate with the magnetic beads to capture the PCR inhibitors.

5. Remove the beads with a magnet and aspirate the supernatant containing only the pure, ready-to-use sperm DNA.

Feature and Benefits

● Streamlines the DNA extraction process: By reducing the number of steps, the Sexual Assault Casework DNA Purification Kit simplifies the DNA extraction process and reduces the potential for contamination.

● Improves DNA quality: Our kit’s one-of-a-kind design guarantees that the final DNA sample contains 95% high-quality male DNA, ensuring more accurate analysis results.

● Easy to use: The kit is user-friendly, and the instructions are straightforward, making it suitable for both experienced and novice forensic scientists.

● Cost-effective: Compared to traditional DNA extraction methods, the Sexual Assault Casework DNA Purification Kit is a more affordable option, making it an excellent choice for forensic labs and law enforcement agencies.

Applications

● Criminal investigations: The high-quality DNA extracted using the Sexual Assault Casework DNA Purification Kit is ideal for use in criminal investigations, helping to identify suspects and build strong cases.

● Evidence analysis: The kit is an excellent tool for analyzing evidence in sexual assault cases, providing a reliable source of DNA for forensic analysis and profiling.

● Cold case investigations: The kit is also useful in the reexamination of cold cases, providing a fresh source of DNA for analysis and potentially leading to new leads and suspects.